Display devices such as LCSs and light emitting diodes (LEDs) are well known in the art having applications ranging from wrist watch displays to calculators. One disadvantage of these devices is that in order to read the display, an observer must be oriented in a fairly narrow viewing angle. This is a disadvantage when the display is located, for example, in a fixed location in a machine control panel. Depending upon the height of the observer and the viewing distance, optimum viewing of the panel is achieved only by some additional compensations by the observer. It would be desirable to make such display devices more readily viewable. According to one embodiment of the invention, the relatively narrow viewing angle of a liquid crystal display is effectively increased by producing a reduced real or virtual image by introducing a demagnifying optical component into the display.
It is known in the art to increase the viewing angle of an LCS by optimizing luminous response as disclosed in U.S. Pat. No. 4,126,382. A liquid crystal cell is formed between two polarizing devices. Short duration pulses are applied to the device, creating a near-optimum luminous response. In U.S. Pat. No. 4,443,819 a magnifying lens is positioned in front of an LCS panel used in a television system. The lens magnifies the image on the display area and reduces the field of view. Another magnification technique is described in U.S. Pat. No. 4,365,869 wherein multiple lens plates project an image from an LCS onto a large screen. This method will also reduce the field of view. U.S. Pat. No. 4,367,467 discloses an LCS assembly which uses an optical assembly located between the liquid crystal layer and the display plane to improve display parallax.
None of the above prior art references discloses an image bar type of display incorporating a demagnifying optical component.